A subwarhead of the above type has been in the Swedish patent 86 01423-0.
In accordance with the characteristic features of the subwarhead described in the above patent the target detector is arranged pivotably on a bearing shaft which is parallel with the line of symmetry of the active part in order to allow pivoting out of the target detector from a folded position, in which the optical axis of the target detector coincides with the line of symmetry of the active part, to a folded position, in which the optical axis of the target detector is parallel with the line of symmetry of the active part, in order to allow a free view of the target detector at the side of the active part. Furthermore an aerofoil is pivotably arranged on a bearing shaft which is also parallel with the line of symmetry of the active part in order to allow pivoting out of the aerofoil from a folded position to a folded position at the side of the active part.
By means of an expedient aerodynamic design of the subwarhead and the braking area of the detector and the aerofoil, a suitable rate of descent of the subwarhead and furthermore a driving moment, which imparts to the subwarhead its rotation, around the axis of spin are obtained. This is brought about without assistance from a parachute, which is an advantage since the parachute takes up space. Within the available space in a carrier shell, an increased space can instead be made available for the active part itself.
Although the subwarhead described above has proved to have good characteristics as far as rate of descent and scanning rotation are concerned, it has become desirable to be able to further increase the braking area. This can be the case, for example, when it is desired to use heavier active parts. The braking area of the target detector and aerofoil is limited to the cross-sectional area of the cylindrical subwarhead, which can result in the rate of descent becoming too high with the existing size of the braking area if the weight of the active part is increased at the same time.